package com.sh.stack;

/**
 * @ClassName ArrayStackDemo
 * @Description TODO
 * @Author yaoqiang
 * @Date 2020/11/5 13:29
 * @Version 1.0
 */
public class ArrayStackDemo {
    public static void main(String[] args) {
        ArrayStack arrayStack=new ArrayStack(3);
        arrayStack.push(1);
        arrayStack.push(2);
        arrayStack.push(3);
        arrayStack.list();
        arrayStack.pop();
        arrayStack.pop();
        arrayStack.list();
    }
}

class ArrayStack{
    private  int maxSize;//栈的大小
    private int[] stack;//数组模拟栈，数据就放在该数组
    private int top=-1; //top表示栈顶，初始化为-1
    //构造器
    public ArrayStack(int maxSize){
        this.maxSize=maxSize;
        stack=new int[maxSize];
    }
    //栈满
    public boolean isFull(){
        return top==maxSize-1;
    }

    //栈空
    public boolean isEmpty(){
        return top ==-1;
    }
    //入栈
    public void push(int value){
        if (isFull()){
            System.out.println("栈满");return;
        }
        top++;
        stack[top]=value;
    }
    //出栈
    public  int  pop(){
        if (isEmpty()){
            throw new RuntimeException("栈空");
        }
        int value=stack[top];
        top--;
        return value;
    }
    public void list(){
        if (isEmpty()){return;}
        for (int i=top;i>=0;i--){
            System.out.println(stack[i]);
        }
    }

}
